Loans and Leases - Schedule of Activity In The Allowance For Loan Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 47	$ 41	$ 46	$ 37
Provision for loan losses	4	2	8	6
Charge-offs	0	0	(3)	0
Ending balance	51	$ 43	51	$ 43
Loans and leases, allowance for losses	51		51		$ 46
Commercial and Financial
Allowance for Loan and Lease Losses [Roll Forward]
Loans and leases, allowance for losses	8		8
Commercial and Financial | Senior Secured Bank Loans
Allowance for Loan and Lease Losses [Roll Forward]
Loans and leases, allowance for losses	$ 43		$ 43		$ 35